Supplements increase mortality in older women?

A study just published in Archives of Internal Medicine called, "Dietary Supplements and Mortality Rate in Older Women: The Iowa Women's Health Study," states:

"Researchers assessed the use of vitamin and mineral supplements in relation to total mortality in 38 772 older women in the Iowa Women's Health Study; mean age was 61.6 years at baseline in 1986. Supplement use was self-reported in 1986, 1997, and 2004 questionnaires. Of the 15 594 deaths (only 40% of the sample size because they were unable to obtain the death records of many of the subjects) identified through the State Health Registry of Iowa, the a multivariable adjusted proportional hazards regression model, the use of multivitamins absolute risk, vitamin B6, folic acid, iron, magnesium, zinc, and copper were associated with increased risk of total mortality when compared with corresponding nonuse (the risk being the strongest with supplement iron).

Bonnie & Steve - not surprisingly, the media failed to mention how the supplements positively affected the subjects. We thought we would mention it. Here is a direct quote from the study:

"Compared with nonusers, supplement users had a LOWER prevalence of diabetes mellitus, high blood pressure, and smoking status; a lower BMI and waist to hip ratio; and were less likely to live on a farm. Supplement users had higher educational level, were more physically active, and were more likely to use estrogen replacement therapy. Also, supplement users were more likely to have lower intake of energy, total fat, and monounsaturated fatty acids, saturated fatty acids, and to have higher intakes of protein, carbohydrates, polyunsaturated fatty acids, alcohol, whole grain products, fruits, and vegetables."

So why was there no mention about supplemental benefit for many of these lifestyle factors? The lead researcher of the study has published negative, questionable research on supplements before, only to be proven wrong years later (i.e. beta carotene and vitamin A).

There were several factors in the supplement group that needed to be addressed: taking synthetic estrogen, not eating enough monounstaurated fat, eating too much polyunsaturated (inflammatory) fat, and eating too many carbs. All of these factors contribute to heart disease and cancer. It is fascinating to note that when researchers excluded supplement users who had CVD and diabetes, the supplements did not show any adverse affect on mortality. So, in essence, the supplement users were better off than the nonusers based upon the aforementioned lifestyle factors.

What does this say? That researchers can extrapolate data however they see fit, especially from a questionnaire-based study. For example, we can extrapolate from this study that if you looked solely at supplement users who were most likely to take synthetic estrogen, most likely to eat inflammatory fats and carbs, and who ate the least amount of monounsaturated fats, we guarantee that mortality risk would skyrocket. Even more egregious is that the researchers did not remove subjects who used synthetic estrogen, which has been linked to a greatly increased risk of CVD and cancer. This should be enough to discredit the study outright.

One other issue: we do not know what brands of supplements these subjects were on. If many of them were on brands such as Centrum, who knows. We do not consider those healthful supplements.

The media did get what it needed, however. Any time they can jump on a study discrediting supplements, they are all over it.

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Statement by Duffy MacKay, N.D., vice president, scientific and regulatory affairs, Council for Responsible Nutrition: “Dietary supplements are used by more than 150 million Americans in combination with other healthy lifestyle habits such as trying to eat a healthy diet and exercising regularly. Research consistently shows that dietary supplement users are higher educated, have higher income levels, and are more likely to engage in other healthy practices than non-supplement users. This study did not discount those facts, and expressly noted that supplement users were more likely to be physically active, more likely to have a lower BMI and waist-to-hip ratio, and have a lower prevalence of smoking, high blood pressure, and diabetes mellitus. The authors note in their article that ‘…dietary supplements are commonly taken to prevent chronic disease…’ The statement would be more accurate with the addition of one word: dietary supplements are commonly taken to help prevent chronic disease. In other words, dietary supplements should not be expected, in and of themselves, and without the synergy of other healthy habits, to prevent chronic disease. This study, however, attempts to tease out one piece of the healthy equation for good health—dietary supplements. CRN maintains that nutrients may be robbed of their beneficial effects when viewed as if they were pharmaceutical agents, with scientists looking to isolate those effects, good or bad. It’s important to keep in mind that this is an associative—not a cause and effect—study. Further, the authors themselves have noted additional limitations. In fact, when the authors did their initial [minimum adjusted] analysis, it appears they actually found benefit for many of the supplements, not just calcium; yet instead of stopping there, they went on to “further adjust” the data, possibly until they found statistics worthy of this publication’s acceptance. The study may make for interesting scientific water cooler discussion, but certainly does not warrant sweeping, overstated concerns for elderly women. Further, the authors show their own bias with this statement: ‘We recommend that they [dietary supplements] be used with strong medically-based cause, such as symptomatic nutrient deficiency…’ which basically means these researchers would rather wait till we all get scurvy before acknowledging any need for supplemental nutrients. Our advice to consumers: your best chance for living a long and healthy life is to engage in healthy lifestyle practices, and many in the scientific community maintain that rational, reasonable use of vitamins and other supplements is part of that equation. Talk to your doctor, or other healthcare practitioner, if you have concerns—but read between the lines of individual studies and don’t make your decisions—either for or against supplements—based solely on hype.”

Statement by Steve Mister, president and CEO, Council for Responsible Nutrition: “Consumers continue to look for the best way to live long and healthy lives, and as much as we would like for science to easily give us answers, the fact is that science is not black and white. But even more concerning is the recent drive to combine political agendas with what should be pure science. The supplement industry regularly gets accused of this practice—in some cases rightly so—yet medical journals seem to be given a pass, as if somehow they held no bias whatsoever. Let’s look at some of the facts in this publication. First, within the article itself are a number of opinions including this one: ‘Also, cumulative effects of widespread use, together with food fortification, have raised concern regarding exceeding upper recommended levels…’ It’s quite popular these days to talk about overnutrification, but in fact research consistently shows that most people are falling short in several key nutrients such as potassium, calcium, vitamin D, and fiber while certain subpopulations fall short in folate, vitamin B12, and iron. Second, the authors advise that dietary supplements only be used ‘with strong medically-based cause, such as symptomatic nutrient deficiency…’ Given the high dosages of iron reportedly being used by the women in the study— iron is the supplement for which there was the strongest negative association—it is highly likely the participants were taking the high dosage of iron reported in the study under a physician’s care for an iron deficiency which may itself have resulted in a shortened lifespan. But the piece purports to warn against over-the-counter use of vitamins. Next, the publication invited a commentary from a scientist whose opinion on supplements and their potential role in good health is already well-known, and whose own work has been the subject of controversy in scientific circles. In the spirit of true scientific discourse, wouldn’t it have been more appropriate to invite a commentary from a researcher who might have looked at the data in its entirety, with sufficient lead time, and provided a different perspective? The commentary states: ‘…Therefore, we believe that politicians and regulatory authorities should wake up to their responsibility to allow only safe products on the market.’ Critics of dietary supplements will continue to advocate that vitamins and minerals should be regulated like drugs, but even they should realize that although drugs undergo rigorous RCT testing, many safety issues for drugs still do exist. Furthermore if nutrients were regulated like drugs, the cost and availability of supplements would make it difficult for average consumers to make these products part of their healthy lifestyle. The editors add their own ‘editorial note,’ using this study as an opportunity to bemoan the fact that ‘A better investment in health would be eating more fruits and vegetables, among other activities.’ This recommendation comes despite the fact that we don’t see a lot of RCTs for fruits or vegetables either. Even without RCTs, we agree that people should be eating more fruits and vegetables; however, in a practical world, consumers are not doing that, and dietary supplements are an option—not a substitute—for getting some (not all) of the health benefits from fruits and vegetables. It’s time scientific journals acknowledge they have some biases, just like industry.”